Risk factors for the development of acute lung injury in patients with septic shock: an observational cohort study

Introduction

Almost one-half of patients with septic shock develop acute lung injury (ALI). The understanding of why some patients do and others do not develop ALI is limited. The objective of this study was to test the hypothesis that delayed treatment of septic shock is associated with the development of ALI.

Methods

An observational cohort study in a medical ICU in a tertiary medical center. Patients were prospectively identified with septic shock who did not have ALI at the outset, excluding those who denied research authorization. There were no interventions.

Results

High-frequency cardiorespiratory monitoring, arterial gas analysis and portable chest radiographs were reviewed to identify the timing of ALI development. Risk factors present before ALI development were identified by review of electronic medical records and were analyzed in univariate and multivariate analyses. Seventy-one out of 160 patients (44%) developed ALI at a median of 5 (range 2–94) hours after the onset of septic shock. Multivariate logistic regression analysis identified the following predictors of ALI development: delayed goal-directed resuscitation (OR = 3.55, 95% CI = 1.52–8.63, P = 0.004), delayed antibiotics (OR = 2.39, 95% CI = 1.06–5.59, P = 0.039), transfusion (OR = 2.75, 95% CI = 1.22–6.37, P = 0.016), alcohol abuse (OR = 2.09, 95% CI = 0.88–5.10, P = 0.098), recent chemotherapy (OR = 6.47, 95% CI = 1.99–24.9, P = 0.003), diabetes mellitus (OR = 0.44, 95% CI = 0.17–1.07, P = 0.076) and baseline respiratory rate (OR 2.03 per standard deviation, 95% CI = 1.38–3.08, P < 0.001).

Conclusion

When adjusted for known modifiers of ALI expression, delayed treatment of shock and infection were associated with development of ALI.